Fiber board of felted interlaced fibers



7 June 30, 1925.-

' J. K SHAW FIBER BOARD OF FELTED INTEBLACED FIBERS Filed March 26, 1920 2 Sheets-Shet 1 '4 gwvc ml'loz L/EhnE/Shaw, y

I I l tter/W 3- June 30, 1925 1.- K.. SHAW FIEEH BOARDMOF FELTEDlNTERL ACED FIBERS Filed March 26, 1920 w/mzcs/za b 2 snts-sheet -2 llatented dune 3th lldfsiti.

aonn a; straw, or mmnnaroms, MINNESOTA, ns'sreinou so 0.

DAHLBER-G, OF

ST. PAUL, MINNESOTA FIBER BOARD OLE FELTED INTERLACED FIBERS.

Application filed March 26, 1920. Sriel No. 368,995.

T 0111i whomit mag/concern: O Be it known that 1, JOHN K. SHAWL, a citizen of the l nitcd States, residing at Minneapolis. in the county ot-Hennepin and St to of Minnesota, have invented certain new and useful Improvements in Fiber Boards of Felted Interlaced Fibers; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This composed of felted interlaced fibers, and has for its object to provide a board of this 1 character which will be more ellicient in use and less costly to manufacture than those heretofore proposed.

With these and other objects in view the invention consists in the novel details of construction and combinations of parts constituting the board, all as will be n ore fully I hereinafter disclosed and particularly point ed out in the claims.

Referring to the accoi'npanying drawing-s forming a part of this specification in which like numerals designate like parts in all the views v Figure l is a diagrammatic sectional view of an apparatus suitable for making a fiber board in accordance with this invention;

Fi ure 2 is a dia rannnatic view illustlace upon the individual fibersf ith i Figure 4 is a diagrammatic sectional View of a fiber bbard made in accordance with this invention and before it passes the finishinn rolls; and

Figure 5 is an enlarged diagrammatic View of a bagasse or analogous fiber of which this board is composed.

In order that the precise invention may be the more clearly understood it is said: I am well aware that various fiber sheets and other articles have heretofore been made from bagassc and'similar fibers, which are by nature provided with a pithy substance, but in so tar as I am aware, all of such fibers have been deprived of the-i1 3 pith be 'lore being manufactured into sheets, and therefore, prior to this invention no one has invention relates to fiber boards utilized the true felting action of these pith like protubcrai'ices on the fibers, to make a stronger and better board as is done in this case. But in order to cause a true interlocking; or felting action between the fibers, special machinery is required, such is disclosed in the drawings, and as the novel structure of this board will be best under stood from a description of the operation of said machinery 1 will disclose the same as follows: i

1 indicates any suitable tank for holding the stock consisting of water and cooked. fibers, 2 the bottom of said tank, 3 an inclined false bottom located above the bot tom 2, l a roll or drum near the lower end of said false bottom 3, 5 aplurality of supporting rolls, (5 a guide and compression roll adjustable on the slide, or other movable means 7, 8 a guide roll similar to the roll 4-, and 9 a guide and tensioning rolladjustable on the means 10. Passing over the rolls just mentioned is the endless foreminous belt or surface 11, conveniently made of wire cloth, and having the oppositely moving portions or'runs 12 and 13.

Between the runs 12 and 13 is located the water outlet 15, provided with the control ling means or gate 16 which may be'suitably manipulated as by the handle or other device 17.

oading with the foraminous surface or belt ll, and in close proximity thereto as regards one portion thereof, is the loraminous belt 18, passing over and around'the series of guide rolls 19, 20, 21, 22, 23 and 24. Said belt 18 also passes over the compression and guide roll 25 coacting with the compression roll 6, andv adjustably mounted on the movable means 26. 27 represents a tension and guide roll, adj'ustably mounted on the means 28, and 529 an outletl'or thewater passing through the belt 18, controlled by the gate 30 and adjustable through the handle 51. 32 and P523 represent suitable water seals made of flexible material for the belts l1 and '18 respectively.

35 represents a channel or passage for water and fibers which may be maintained at any desired hydrostatic head 3 37 an opening from the channel 35 into the tank space orchamber 3S, and 39 a top or partition separating said chamber or space 38 from the remainder of the tank. e0 repre sents a second channel for, water and pulp the same as is described and claimed in my copending application, Serial Nun'iber 368990, filed March 526, 1920, Patent No. 1,532,083., dated March 31, 1925, and en titled Process of and apparatus for making fiber boards. I i

The operation of this machine will be understood'from what follows:

It is preferred to use long fibers, but of course fibers'of any usual length niay be employed. By reason of the direction of flow of the water through the chambers 38, 43 and 48, and'by' reason of the'nat-ural tendency of the flowing water to laterally separate said fibers, the latter will be brought into positions more or less parallel to each other, and more or less perpendicular tolthe line of travel of the surface 13, while at the szimetime all of said fibers will occupy positions more or less staggered with relation to their neighbors as shown. aecordinglya large percentage of the forward ends 61 of said fibers will first contact with said surface 13, and will be carried along by the belt from the positions shown n Figure 2 to those shown in Figure 3, for the rear ends 62 of said fibers will have laggedv behind the front'ends 61, in the water, so' that the front row of said fibers assumea' The sec-',

somewhat curved or bent shape. 0nd row, or those fibers 63 immediately following, and which have not reached the surface 13, but have reached the rear ends 63 of the fibers 60, are now forced by the oncoming water to contact at their forward ends against the curved fibers 60. And as said fibers (33, originally, due to their paral-' lel positions as shown at 68 in Figure 2,

were more or staggered or interlaced with the fibers before the latter became curved. it is evident that this interlacing or entangling action between the fibers 60 and 63 will beenhanced or increased by the oncoming Water after said curvature takes lace.

It results from the actions just described. that said fibers 63 become themselves more or less curved. indicated in Figure 3, due to the transverse movement of the fibers 60,

. and that a third row of fibers G4 which are also interlaced or staggered with the fibers (53 will hecon'ie in time curved and ontangled with the fibers 0 and 63 that have Lee-Lo portions of the sheet.

preceded said fibers iii. thus results that owing to the lloatin;- of the fibers into parallel, interlaced or sta and positions, and in a direction tlfll15\',fit to the traveling surface 175, the entanglement o l the fibers is continuous between successive rows; and.

the pressure oi. the water arises the whole to be very loosely assembled in their interlaced positions on said surface, thus forming an open mass of fibers more compact next to the wire than avay from it. This mass is carried through the opening 70 into the space 4.3, With one or more partially curved and partially entangled layers sinnlur to the fibers (i0 and 63 clinging to it.

In said chamber orspace 43, other fibers similar to the fibers 64 become interlaced and entangled with the layers on the belt, and the process of entanglement and massing proceeds as be'tore.- in the incantiu'ie layers of fibers in all respects similar to the layers 60, 68'and 64 are interlaced, entangled and massed on the traveling belt 18 from the space or chamber 48. This second of fibers are carried through the opening 71 by the belt 18 in a condition similar to the first mentioned mass that passes the opening 70, and the fibers in the space 43 interlacc, und'beeomc entangled with sa d second with said first mentioned mass. The result is, owing to these parallel and staggered relations, the fibers in the space 43-3 constitute a. third mass of, fibers which are interlaced and entangled with each other, as well as with each of said firstnamed masses.

As a result of the foregoing entangle merits of the various fibers and the motion of the surfaces 13Kand 18. the mass of fibers are carried through the opening 75, between the compression or con'ipacting rolls 6 and 25, and is formed into the sheet or board 76, all as will be readily understood.

An important feature. of this invention resides not only in being able to thus interlace, or entangle, the fibers in the body of thesheet, but also in being able to vary the l intl.,size,-und class, of fibers in different That is to say, I may feed to the channel 3:"), one kind of fibers, .whichhmy be relatively short or more expensive fibers than are those fed to the channel 4-0, and I may feed to the channel 45, the same class of fibers as are fed to the channel 35, or I may feed a totally dillercnt class of fibers. In other words I may provide as many channels 35, 40 and 45. as there are ditlerent characters of fibers in the finished board, and 1 may place in the first channel 35 and in the last'channel 45 any characters of fibers I desire, whereupon the board will he provided with an outer layer '7'? corresponding to the fibers that are fed to the channel 35, with another, outer layer .i I I F mass in a manner similar to that-described lIl' connection Ill] '78 corresponding to the fibers that are fed. to the. channel 45, and. with one or more intermediate layers 79 corresponding to the character of the fibers which are tied to the channel ll) and to any other channels which may be located intermediate oi"? the channels 35 and 4H.

In milking this board i prefer to use bugeese and other pith carrying fibers such as those from cane, bamboo, sorghum, etc, and which have been treated according to the process disclosed and claimed in my copending application, Serial Number 368993 filed March 26, 1920, Patent No. 1,501,925 dated July 22, 1924:, and entitled lhigesse fiber and process of producing the same. In brief such process which co sis in dissolving out the binding n'nrter'l between the fibers as well as the brittle material encasing the fibers, without impairing the original strength of the fibers, and, also, Without dc n-iving be individual fibers of their pith like protubcrzinces, or knots, which are so valuable as n felting agency as Well as for use as a bout insulating means. Further by controlling the action in the heating engine, and the stren 'tl'i of the dissolving solution, the size of the bundles of fibers can be controlled, and therefore the heat insulating? ltiherefore follows th at u'hen the: b'ers:v (30 provided. with the pith lilo pr'otuberuno'es 100 and the book like portions 101 are terluced in the man-nor disclosed, they liecome so lirinly interlocked that this'feltinif action resembles that/of Wool more nearly than it does the so celled felting of cotton and wood fibers. So pronounced is this difference of structure that nctuul tests have shown that :1. fiber bozrrd constructed us above disclosed, and only loosely oon'ipoc ell, so as to include 21 large number of air cells to serve u lieutinsulating medium, is very much stronger both as to tensile strength und breuking strength than is it similar board made from wood, flax or other fibers. In other words, even when this board is subjected to transverse breaking; strains the book like portions and the pith like pro- (ill jcctions on the il'idividuul fibers interlock and thus prevent the fibers from slipping over each other, ivitli the result that a large. number of the libers are strained longitudinally instead oi transversely of their length and thus is the strength of the board. very greatly increased.

But the greatest di i'crencc between thi. board and the prio boards zrppenrs w en the fibers are compacted with a heavy pressure or soy s00 lbs. to the square inch. Such. a pressure produces u board which is hard and resilient like wood. in fact it may be whittled, sawed and nailed like Wood and constitutes :1 valuable substitute the higher grades of hunber for the menutwture of trunks 'fiuruiture. etc. Actual have shown it'to possess a: tensile strength of While a very much smaller proportion, say

10% escapes through the. opening 29. The gut-es l6 and 30 are conye-niently manipulated to eilect this division of the water, while nmintainirug the desired proper steady flow tlu'mlgb the surfaces 13 21111118 to produce the desired results. But of course the proportions of Water that escupe through the two OPQDiHQJS mentioned may be widely varied according to the results sought in the finished board.

The rolls ii and 25 are readily adjusted by the menus illustrated to produce any desired compression in tllcopenings between suirl rolls, that the libel board may be giyco any desired degree of porosity. In

relatively large fibers in the rural Ill) end relatively line lib rs in the ole 4 5,5 unrensbled to control the uir spaces in thobodyof the board, and thereby to control its beat-insulating qualities. Q

lhehcuds 3631511161 46 of the liquid in the channels 35, Q0 and so are so nuiintained that there Will-be a minimum tendency of liquid to flow between the 'chaiubers or spaces 38, l3 and 48. In other Words, the pressures of the liquid in the lust mentioned chambers are maintained as nearly equal as possible, and those iuiuinuun tendency of the tillers to mix in the said spaces is secured. The interlacing process is facilitated by the fact that the openings 37, 42 and 47 are of a less area thanure the spaces 38, 4:3 and 38 into which the fibers are led. In other words the fibers must first pass through the openings at s relativclyhigb velocity and close relation to oucl other; and they are then immediately released into a wider space Where they take on u lesser velocity, and naturally spread out as they pass along with the we. thus assuming-the parallel relations int-nested in Figure 2.

llt will now be clear that my board is composed of dill'erent layers of interlaced. pith. carrying fibers which produce not only a true felting, or entanglingactiou, but. also, high heat insulating qualities owing to the pith particles being largely composed of closed ui r cells. So great are the advantages o'Z these pith like protuberences that l find that an excellent product can be produced with other fibers so long as say 20% or more of ihe'board COHSlr: sot these said pith carrying fibers. V v

it is obvious that those skilled in the art may vary the details of the invention without departii'ig from the spirit thereof, and therefore i do not wish to be limited to the above disclosure except may be required or the claims.

' What 1 claim is 1. The herein descril'iod fiber board coinposed of difi'erent lnasses of ditlferent kinds ol fibers, a portion of the fibers of each of said masses interlaced with a portion of the fibers of an adjacent mass, and a portion of said fibers carrying natural pith like protuberances serving as entangling agents between the fibers.

The her! in described fiber board composed of different masses of dill'erent kinds of fibers, a portion of the fibers of one mass i being interlaced. with a portion of the fibers of an adjacent mass, and more than twenty per cent of said fibers carrying natural pith like protube 'ances' serving as inter-entangling-n'ieans between the fibers.

3. The herein described fiber board composed of different masses of difi'eren-tkinds of pith carrying fibers interlaced with each other, said fibers carrying their pith in the and one mass of said fibers being of a quality difi'crent from anothermass.

The herein described heat insulating fiber board'coinposed of different masses one of which composed of bagasse fibers carrying its natural pith, the fibers of adjacent .niasses interlaced with each other, and one of said masses composed of larger aggregates of fibers than another mass in order to provide larger air cells between the masses.

(3. The herein described fiber board devoid of a peeling structure and composed of different masses of bagasse fibers interlaced with each other and carrying their natural ith, said fibers and masses being highly compressed together to form aboard of a high tensile and breaking strength for use vas a substitute for lumber.

e In testimony whereof 1 ailix my signature. I

JOHN K. SHAXV. 

